Survival of Escherichia coli O157 in faeces of experimentally infected rats and domestic pigeons.

In order to evaluate the role of some synanthropic animals in the spreading of Escherichia coli O157, laboratory rats and domestic pigeons were experimentally infected per os with E. coli O157. Rats infected with 10(5) colony forming units (cfu) (n = 5) and 10(9) cfu (n = 5) shed E. coli O157 for 2 +/- 1.7 d and 9.8 +/- 1.3 d, respectively. In the faeces of infected rats stored at 4 degrees C in a moist environment, at 4 degrees C in a dry environment or at 20 degrees C in a moist environment, E. coli O157 survived for 34 weeks. When stored at 20 degrees C or - 20 degrees C in a dry environment, E. coli O157 survived for greater than or = 36 weeks. Pigeons infected with 10(5) cfu (n = 5) and 10(9) cfu (n = 5) shed the pathogen for 14.8 +/- 3.4 d and 20.2 +/- 5.2 d, respectively. Both species, rats and pigeons, can be important in spreading of the E. coli O157 infection in cattle.